Arrangement in beater cylinders for threshers



Dec. 2. 1969 s. STOKLAND 3,481,344

ARRANGEMENT IN BEATER CYLINDERS FOR THRESHERS Filed Sept. 1, 1967 INVENTQE SI MQ STOKLAND United States Patent 3,481,344 ARRANGEMENT IN BEATER CYLINDERS FOR THRESHERS Sigmund Stokland, Brumunddal, Norway, assignor to Gebr. Claas Maschinenfabrik G.m.b.H., Harsewinkel,

Westphalia, Germany, and A/S Den Norske Remfabrik, Kolbotn, Norway Filed Sept. 1, 1967, Ser. No. 669,349 Claims priority, application lglorway, Sept. 7, 1966,

64,59 Int. Cl. A01f 12/20 US. Cl. 130-27 4 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to threshers for grain and the like and more particularly to a beater cylinder used with such threshers.

Beater cylinders are previously known including a plurality of beater bars secured to and evenly distributed about a rotatable shaft and radially spaced therefrom so as to during rotation cooperate with a grate concave, and in which there in the space between adjacent beater bars in the axial direction is secured a strip shaped sheet of elastic yieldable material having in cross-section convex curved outer surface with a radius substantially corresponding to the maximum working radius of the beater bars.

The object of the above named strip shaped sheets secured in the spaces between adjacent beater bars is to prevent the grain separated in beating the material to be threshed against the concave from moving into the spaces between the beater bars as it impinges the outer curved surface of the elastic yieldable material which lead said grain through the grate concave and press the material against the surface of the' concave so that grain left in the material is removed therefrom by friction. Threshing cylinders of the type above referred to give satisfactory results with respect to the threshing proper at the same time as the power consumption in rotating the cylinder is reasonable during usual conditions.

However, practice has shown that if the rear of a beater bar trails a considerable quantity of threshing material or straw which is compressed between the surface of the grate concave and the elastic yieldable strip forming a depression in the latter, a convex wave is formed in the strip between said depression and the subsequent beater bar corresponding to the peripherical shortening imparted to the strip by the radial depression of the leading portion thereof, and said wave easily will contact or strike against the surface of the grate concave resulting in that not only the power consumption increases but also that the strip quickly is destroyed.

The object of the present invention is to provide a threshing cylinder of the type referred to by means of which the above drawbacks are removed.

According to the present invention this is attained thereby that each of the convex curved strip shaped Cir 3,481,344 Patented Dec. 2, 1969 sheet of elastic yieldable material, having its centre of curvature in the axis of the cylinder, is connected to an inwardly spaced and parallel thereto extending rigid sheet shaped support member by means of flexible, not stretchable and radially directed connections, the circumferential spacing of which corresponds approximately to the radial space between said strip shaped sheet and the support member.

By this arrangement it is prevented that a local depression in the elastic yieldable sheet effected by said trailing material or by the passing of foreign bodies, may be able to form a subsequent wave owing to that the not stretchable connections retain said elastic yieldable sheet and ensure that no part thereof moves beyond the maximum working radius of the beater bars, but allow necessary yielding of said sheet.

An embodiment of the invention is, as an example, illustrated in the accompanying drawing in which:

FIG. 1 is a cross-sectional end view of a beater cylinder of the instant invention and the operatively associated concave grate thereof, and

FIG. 2 is a fragmentary cross-section end view, in greater scale, of the elastic yieldable sheet connected to the support member.

In the drawing 1 denotes the shaft of the threshing cylinder about which, by means of spiders or disc-shaped support members 2, a plurality of beater bars 3 are secured in evenly distributed and radially spaced relationship. The heater bars 3 cooperate with a grate concave 7 consisting essentially of bars 8 parallel to the shaft 1 and defining interstices 8 said concave being positioned in relation to the maximum operating circle X of the beater bars so that between said circle and concave a gap 9 is formed having a radial height decreasing slightly from the inlet to the outlet of said gap, the material to be threshed being fed into the gap in the direction of the arrow A.

As shown in the drawing the spaces between adjacent beater bars 3 are closed by elastic yieldable strips or sheets 4 of rubber, plastic or the like having an outwardly curved surface with a radius from the axis of rotation of the cylinder approximately equal to the radius of the operating circle X of the beater bars 3. The strip or sheet 4 extends over each length of the beater bars and the edge portions thereof are secured to the mounting means of the respective beater bar as described below.

According to the invention each strip or sheet 4 of elastic yieldable material is connected to a support membet 5 arranged at a selected radial distance inside said sheet 4. The supportmember 5, consisting of rigid sheet material such as sheet metal, hardened plastic or the like, extends parallel to the sheet 4 the longitudinal rims of which through inclined portions 4' are secured to said support member 5, as shown. The curved portion of the strip on sheet 4 of elastic yieldable material spaced radially from the support member 5 is connected thereto by means of a plurality of radially directed and in the whole length of the sheet 4 extending spoke-like connections 6 of flexible but not stretchable material, such as rubberized cord or the like.

The connections 6 preferably may consist of a rubberized textile web which is square waved and of which the top and bottom portions 6 are secured, such as by vulcanizing, to the inner surface of the sheet 4 and the adjacent surface of the support member 5, respectively, as shown. Thus elastic sheet 4 is allowed to yield locally inwardly but prevented from moving outwardly beyond the original distance from the support member 5.

The distance between the sheet 4 of elastic yieldable material and the rigid support member 5 is selected as small as possible, thus a distance corresponding approxi- 3 mately to about 10-20% of the radius of the cylinder has shown satisfactory results, and the circumferential spacing of the radial connections 6 may be chosen within the range of from 0.5 to 2 times the distance between the sheet 4 and support member 5.

In the embodiment shown each individual strip or sheet assembly, including the elastic sheet 4, the sheetshaped support member 5 and the connections 6, constitutes an arch having an axial length corresponding to the length of the cylinder and a circumferential width adapted to the distance between adjacent beater bars 3 so that the edge portions thereof may be secured to the inner side of the respective beater bars, or between a clamping plate secured thereto, and a clamping member 11 secured to the plate 10 by means of screws 12.

As will be understood, the rigid support members 5 may be formed in one piece having the shape of a rigid cylindrical drum on the surface of which the sheets or strips 4 are secured in the above described manner.

In mounting the elastic yieldable strips or sheets on rigid support members interconnected by flexible but unstretchable connections according to the present invention, it is assured that in connection with a possible accumulation of material dragging rear of a beater bar, or by passing of foreign bodies, which effect partial impression of the elastic sheet, no subsequent wave or buckle is formed in the material of the strip or sheet due to the action of the connections 6.

I claim:

1. In a thresher for grain and the like and including a heater cylinder and concave structure, a bar type, rotary separator cylinder comprising: a shaft having an axis, a plurality of beater bars evenly distributed about said shaft and radially spaced therefrom, adjacent pairs of said bars defining spaces therebetween, a plurality of elastic, yieldable sheet means, each sheet means providing an outwardly curved surface extending between the bars of a respective pair, and having a radius of curvature substantially corresponding to the working radius of said bars, a plurality of rigid sheet shaped support means, each support means providing an outwardly curved surface extending parallel to the inner surface of a respective sheet means, between the bars of a respective pair and spaced inwardly from said sheet means, means interconnecting said sheet means and said support means, said connecting means consisting of flexible not stretchable, radially directed members the circumferential spacing of which corresponds approximately to the space between said sheet means and said support means.

2. In a beater cylinder according to claim 1, in which said connecting means, extending longitudinally of the cylinder, consist of a square-waved web of flexible but unstretchable textile material, having the top and bottom portions of said waves secured to the inner surface of the sheet means and to the opposite outer surface of the support means, respectively.

3. In a beater cylinder according to claim 2, in which said web consists of rubberized cord material and is secured to said surfaces by vulcanizing.

4. In a beater cylinder according to claim 1, in which said support means form a cylindrical drum to which said sheet means are connected.

References Cited UNITED STATES PATENTS 2,361,633 10/1944 Jones 27 3,127,898 4/1964 Klemm et a1. 130-27 3,259,134 7/1966 Stokland 130--27 3,410,271 11/1968 Hengen et a1 130-27 ANTONIO F. GUIDA, Primary Examiner 

